Nudibranchs are small marine invertebrates that are found all over the world. There is amazing variation among the different nudibranch species in color, size, body shape, and diet. Let’s look at a few of the nudibranchs that are found in the Indian Ocean.
Casella Atromarginata
The brilliant blue trim against velvety midnight black makes this small nudibranch species stand out and gives it its common name: blue velvet nudibranch. It has a somewhat hammer-shaped body and eats flatworms by sucking them up through a proboscis. It averages about an inch long.
Chromodoris Magnifica
This spectacular nudibranch species of the Indian Ocean has black and white longitudinal stripes over the center of its body, a yellow band all around the edge of its mantle. Its external gills resemble a small tree on its posterior end, with two rhinophores that look like horns on the anterior. These are brilliant orange in color and can be retracted if the nudibranch senses a threat.
Doriprismatica Atromarginata
The striking white and black coloration of this nudibranch species make it stand out. Its body is creamy white or tan with black edging all along its ruffled mantle. Its rhinophores are black and its gills can be beige to black. It is about 2.5 inches long.
Chromodoris Lochi
The sleek blue, black and white body with yellow rhinophores and gills make this 1.5-inch nudibranch stand out. The body is a light sky blue, with a black strip drawn midline, and another going around the edge of the body between the blue main body and the white edging of the mantle. The foot is similarly colored: blue near its body, with a black stripe and a white edge.
Nembrotha Kubaryana
This is a relatively large species, reaching about 4.7 inches long. It has some of the most spectacular coloration of the nudibranch species of the Indian Ocean. It is deep black with electric blue-green longitudinal ridges and gills and an orange border all around the foot and orange rhinophores.
